Iron Flashcards
ferric form
fe3+
ferrous form
fe2+
where does fe2+ sit in haemoglobin
in prophyrin ring
where is the majority of body iron found
in haem
wjere does iron absorption mainly occur
duodenum
what is iron absorption enhanced by
aacorbic acid- vit c
meat and fish
acidic environment
what is iron absorption inhibited by
tannins e.g tea
phytates- cereals, bran nuts and seeds
calcium e.g dairy produce
what does cyctochrome b do to iron
reduces feric iron 3+ to ferrous form 2+
role of DMT- divalent metal transporter
transports ferrous iron into duodenal enterocyte
ferroportin role
facilitates ironn export from enterocyte
passed onto transferrin for transport elsehwere
where is ferroportin highly expressed
on basolateral membrane of enterocytes in duodenum where it transports dietary iron absorbed in intestines into bloodstream
how is iron absorption regulted
via hepcidin- mjaor negative regulator of iron uptake
where is hepcidin produced
in the liver in response to increased iron load and inflammation
MOA of hepcidin
binds to ferroportin and causes its degradation
iron therefore trapped in duodenal cells and macrophages
when do hepcidin levels decrease
when iron deficient
